4. Relief in complete denture Dr Amany Radwan

5. Relief  Relief: It is the elimination or reduction of undesirable forces or pressure from a specific area under a denture base.

6. Relief Area: “ Area in the fitting surface of the denture that is reduced to eliminate excessive pressure.”

7.  Areas to be relieved: I- Hard bony areas. II- Sensitive areas.  Hard bony areas:  Midline of the palate  Maxillary& mandibular tori  Prominent genial tubercle  Sharp Thin bony protuberances on ridge  Sensitive areas:  Incisive papilla  Rugae area  Mental foramen

8. Maxilla  Hard areas: Median palatine rephea Torus palatinus  Sensitive areas:  Incisive papillae  Prominent rugea area

9. Mandible  Hard areas Prominent genial tubercle Torous mandibularis Sharp bony ridges  Sensitive areas Mental foramen

10. Methods of Relief:  I- Direct Relief (Laboratory) a- Scraping the final impression before pouring of it. b-Relief on the cast  II- Automatic Relief (Clinical) a-At the time of impression by using selective pressure impression technique b- Grinding to the fitting surface of finished denture during insertion

11. Shape of Relief Area It is never well defined. It merges into the surrounding fitting denture surface. It depends on the compressibility of the area to be relieved as well as that of the surrounding areas.

12. I-Direct Method 1- Scraping the Impression It is specific for plaster of paris impression

13. 1-Direct Method: 2-Building on the cast before construction of the denture bases by using wax or tin foil on the cast and cementation by cement before processing

14. II- Automatic Relief 1-(Selective Pressure Impression Technique) 1-(Selective Pressure Impression Technique) A- Scraping the compound selectively. B- Secondary impression in Zn/O eugenol or plaster.

15. II-Automatic Method: 2-By grinding the areas should be releaved on the fitting surface of the final denture.

16. Aim of Relief:  Relief of sensitive areas increases the comfort of the patient.  Relief of hard areas improves the denture stability  Prolongs the duration of denture service by compensating for denture settling and some ridge resorption.  Compensate for polymerization shrinkage.